Abstract:
I will present our our new state-of-the-art Messenger Monte Carlo MAPPINGS V code (M ³ ). The turbulent ISM causes inhomogeneity of electron temperature and density within the nebula, which is most effectively modeled through Monte Carlo ray tracing methods. We analyze the dependence of different optical emission lines on the complexity of nebular geometry, finding that the emission lines residing on the nebular boundary are highly sensitive to the complexity of nebular geometry, while the emission lines produced throughout the nebula are sensitive to the density distribution of the ISM within the nebula. Our fractal photoionizationmodel demonstrates that a complex nebular geometry is required for the accurate modeling of H II regions and emission-line galaxies. Finally, I will discuss the opportunities for these types of models for understanding galaxy formation and evolution with the current and next generation telescopes including JWST and the GMT.